1. Field of the Invention
The present invention relates generally to an improved structure for robotic cleaner, and more particularly to a structure of cleaner that can climb a step obstacles or cross over a bump hindrance to negotiate different landforms and move to pre-designated location.
2. Description of the Prior Art
In the wake of the development of science & technology, the application for variety of automation devices have been stepwise bringing in from the machine tools of large and medium size for production in the past to the livelihood products of compactness and precision as an aid to promote the convenience of daily life; therein, the robotic cleaner (the so-called cleaning robot) that can move autonomously is their typical application to the regular household life.
A conventional robotic cleaner, in any case, mainly comprises of a chassis mounted a dust collector with a dust-wiping paper roller or a rotary brush fitted underneath where necessary; also, there will be plurality of moving elements (for example: wheel or caterpillar band) assembled to the periphery around the bottom deck of the chassis to be driven by one of the power devices (motor and transmission gear box) already mounted on the chassis to drive the chassis for movement that allows the dust-wiping paper or the brush to follow the moving path of the chassis to sweep the surface to be cleaned; in the meantime, the dust collector can collect the swept dusts and miscellaneous articles; nevertheless, although the foresaid robotic cleaner can be operable to perform the cleaning on a plane in a manner of autonomous movement, spiral movement, skirting around the wall or zigzag movement, etc.; however, the operator shall give the cleaner a hand by pulling and lifting and helping the cleaner break away from a raised place (such as the sill or the step landforms with level difference) on the surface to be cleaned that fails the continuous movement of cleaner; thus doing not only results in an inconvenience against its use, but also restraints thereof occasion of application; the truly automatic performance is unachievable.
Therefore, the inventor of the present invention filed an Application No. 96100909 for a patent of “A robotic cleaner with climbing function” in this regard in Republic of China that discloses a structure that comprises of a chassis with a structure of dust collector mounted at the center of the chassis; wherein the dust collector is fitted a filter below its suction intake and the periphery of bottom deck around the chassis are fitted with plurality of downward-extending wheels while these wheels are fixed the spherical casters at their base; meanwhile, both opposite sides on the top of the chassis are erected two sets parallel and extending first swing arm and second swing arm respectively that allows the first arm and the second arm to pivotally rotate to stretch outward or retract inward to the chassis through a motor by driving the first gear for stretch and the second gears for retraction in conjunction with a belt to link with two linkages respectively; wherein, the external end of both the second swing arms are mounted a driven wheel that can be at idle rotation while both the first swing arms are mounted a drive wheel so that two motors mounted onto the chassis can transmit the power to these drive wheels respectively by passing through the plurality of advancing gear and a belt that enables the cleaner to retract the first and the second swing arms inside the chassis and allows the drive wheels to touch the ground (to match with each spherical casters) to be actuated for movement when used in a general plane status; when a climbing is desired, the cleaner can have the first and the second swing arms stretch outward and outside the chassis to support and lift the chassis for a certain height, and then actuate the drive wheels to move to overcome the need of moving on a landform of different height.
Even so, the aforesaid structure is to have the power supply (motor) of drive wheel mounted on the chassis and must transmit the power to the drive wheel at the external end of the first swing arm through the belt; therefore, in addition to the plural advancing gears connected to the output end of motor and two belt wheels assembled to the belt ends, the different status of separate rotation between the first swing arm and the belt (belt wheel) shall be overcome separately which makes thereof overall structure extremely complicated; it not only is inconvenient for assembly, but also is burdened the production cost; furthermore, its very difficult disassembly leaves a hard repair and maintenance operation; meanwhile, taking the advantage of belt connection for actuating the power may restrict thereof torque transmission where a higher transmission power is unbearable and a wear is prone to take place and affect the transmission efficiency after being used for a long time.
In the light of the abovementioned imperfection to the conventional robotic cleaner in possession of the climbing function, the inventor creates the present invention mainly focusing on the improvement against the foregoing imperfections.